Nutrient Content of Meat

Meat consists of water, protein, and fat, with a few minerals and some B vitamins. It contains trace amounts, if any, of carbohydrate (liver is the highest source), no fiber, and no vitamin C. Meat is about 75 percent water, and most of this water is found in the muscle cells.

Protein. High-quality protein is the second major constituent of meat, accounting for about 20 percent of its weight. Meat contains 7 grams of protein per ounce. Current recommendations on meat intake suggest 4 to 6 ounces of meat a day, or 28 to 42 grams. The Reference Daily Intake of protein for adults is 50 grams per day, so meat is an excellent source of this nutrient. The remaining protein is usually met by consuming foods from other food groups.

Fat. Fat content can vary widely, according to the grade of meat and its cut. Several cuts of beef are lower in fat than an equal amount of some poultry choices, yet consumers often select poultry over beef, thinking it is lower in fat. The general rule of thumb is that beef cuts from the loin or round, and veal and lamb cuts from the loin or leg, are the leanest choices. Examples of lean beef cuts include sirloin, tenderloin, top loin, top round, and eye round. Lower-fat meats, including some types of wild game, are becoming more popular with consumers. Most processed meats, such as hot dogs, and bologna, are not a good choice for consumers looking to lower fat consumption, because they average 30 to 50 percent fat.

Carbohydrate. Meat contains very little carbohydrate. Glycogen, found in liver and muscle tissue, is present when the animal is alive, but the glucose that makes up the glycogen is broken down to lactic acid during and after slaughter.

Vitamins. Meat is an excellent source of certain B vitamins - thiamin (B₁), riboflavin (B₂), pyridoxine (B₆), vitamin B₁₂, niacin, and some folate. Niacin is obtained from tryptophan, an amino acid plentiful in meats and milk. Lean pork is an excellent source of thiamin (B₁). Fat-soluble vitamins, especially vitamin A, are found in liver. Vitamin loss during meat preparation depends on the temperature, the time exposed to the heat source, and the cooking method. Thiamin (B₁) is especially sensitive to heat, so levels of this vitamin are somewhat reduced in canned meats, which have undergone high-heat processing. Water-soluble B vitamins can be leached from meat into cooking liquid, but can be recaptured by making gravy or soup from that liquid.

Minerals. Meat is an excellent source of iron, zinc, copper, phosphorus, and a few other trace minerals. Liver is especially rich in iron and vitamin B₁₂. Minerals are stable when heated, and although they can be lost in cooking water, retention of most minerals in cooked meat ranges from 80 to 100 percent.